The subject invention relates to an adjustable valve assembly and more particularly to an adjustable valve assembly adapted to accommodate fluid flow in forward and reverse directions at different flow rates responsive to a critical line pressure with the valve being adjustable to vary the critical line pressure at which the flow rate is varied.
In control systems for fluid actuated mechanisms such as hydraulically actuated packer mechanisms for refuse collection vehicles and the like, it often is desirable to provide valves which are adapted to accommodate the flow of fluid in forward and reverse directions at different flow rates responsive to line pressure to provide a predetermined cycling of the mechanism. It has been found, however, that most valves of such type in the prior art are not entirely effective and reliable in the performance of such functions.
As a result of the shortcomings of the prior known valves, the valve assembly of U.S. Pat. No. 4,044,791 owned by the same assignee as the present application was invented and provided a substantial advantage over the earlier control valve devices. However, the valve of the aforementioned patent, while providing exceptionally satisfactory performance under relatively unchanging conditions, is not capable of providing fully satisfactory performance in instances in which the viscosity of the oil employed in the valve varies such as in cold weather or when the valve is used for different purposes under substantially different pressure ranges. On such occasions, it has been found necessary to either completely replace the valve or to disassemble the valve to replace the internal spring components in order to accommodate the changed conditions. The present invention represents an improvement over the invention of the aforementioned patent in that it provides accommodation for a wide variety of pressure and oil viscosity conditions by effecting a simple adjustment of the valve which permits the valve to operate satisfactorily under a new set of pressure and/or viscosity conditions.
Accordingly, it is the principal object of the present invention to provide an improved adjustable valve assembly.
Another object of the present invention is to provide an improved adjustable valve assembly which can be adjusted to accommodate the flow of fluid in forward and reverse directions at different flow rates responsive to a wide range of critical line pressures.
A further object of the present invention is to provide a novel and versatile adjustable valve assembly suitable for use in a control system for a fluid actuated mechanism.
A still further object of the present invention is to provide a novel adjustable valve assembly adapted to accommodate the flow of fluid in forward and reverse directions at different flow rates responsive to line pressure which is suitable for use in the control system for a fluid actuated packer mechanism of a refuse collection vehicle.
Another object of the present invention is to provide a novel adjustable valve assembly which is highly responsive to line pressures for effecting changes in flow rates therethrough in both forward and reverse directions.
A further object of the present invention is to provide a novel adjustable valve assembly which is comparatively simple in design, relatively inexpensive to manufacture and highly effective and reliable in performance under a wide degree of operating parameters.